Cupcake CNC 3G 5D or Ugly Cable Hack help Please

I have borrowed a long neglected Cupcake CNC #1682. I'm trying to go through the machine and upgrade everything. My first priority is to get a stepper extruder on it, however, I have the 3 gen electronics. I realize my only options are the 3G5d shield route or an ugly cable hack. Since I can't find any 3G 5d shields for sale, I have decided to go the ugly cable hack route, unless anyone has a 3G5D shield they'd like to get rid of .

What kind of stepper driver can I use with this? The pololu's aren't really stand-alone drivers like the 3 gen stepper driver boards are, right?

Does anyone have any old electronics they'd like to sell me?

The obvious answer is to just upgrade all of the electronics but I just can't do that right now. the owner of the machine has given me a budget to work to and new electronics won't fit into that.

The next priorities for the machine are a Z-Rider and a lowrider x/y carriage by twotimes.

Any ideas are welcome.

I've done this before with the gen 3 driver. I think a pololu should be fine though. Just match the pin assignments as you would any other stepper driver.

have you seen the gen3+ ?

gen3+ is is a daughter card for the generation 3 mainboard which plugs into the sanguino header, and replaces the extruder controller. The stepper hack is replaced with a Pololu header, and mosfets are provided for hot end and print platform. [koti.kapsi.fi]

Thanks for the pointers, guys. I've found various schematics around these forums detailing how to hook up the existing extruder to use the h-Bridges to drive an extruder. It requires alternate firmware. I am still doing a ton of reading and research on the subject. I was hesitant to even start the thread as I KNOW the information is out there to be had.

Do you have any other pointers for me? Schematics, firmware, etc? I have the printer printing pretty well with the MK5 Plastruder and the MOSFET DC motor hack to keep the extruder motor going. I have a Wade extruder all printed and assembled with a stepper and ready to get installed once I know I can do the software side.

Thanks!

if anything you can do what i did. solder wires to the pins open hole spacing. quite smart of zach h. to include a space for every pin to have a wire to solder.

With gen3+ hack you can just use standard marlin firmware. Same as 95% are using

Thanks, All. I have bought some pololu 4988 stepper drivers with carrier to use. Hopefully they arrive quickly!

Hi, my DC motor died and I'm looking at the same upgrade. Stepper motor and DRV8825 Pololu board on the way. Were you able to get it working? Thanks!

Quote
Dust
With gen3+ hack you can just use standard marlin firmware. Same as 95% are using

Hi Dust, is there anywhere in the US to buy the Gen3+ board already built? Thanks.

bzbee

I did not get far enough to get it working. I accidentally applied 12v to the motherboard on a stepper direction line and fried it. I ended up going to a ramps 1.4 board along with a greg's hinged steeper extruder and couldn't be happier. My cupcake is printing like a champ! I am going to replace the atmega 644 and get the gen3 board going again. I'll turn it into a hand held plastic welding gun using the old mk5 plasterer.

I saw that the makerbot store says they have 3g5d shields in stock but I think they're lying.

Quote
umdpru
... a greg's hinged steeper extruder and couldn't be happier.....

Can you link me to the STL files you printed? Thanks.

First, there is no Greg's Hinged Extruder that will fit the stock cupcake/TOM dino's. I had to custom drill some holes to bolt things together. I didn't really feel like using Solidworks to remix an extruder to fit. Second, I am switching from a MK5 plastruder hot-end to a J-Head. With that said, I used the following parts:

Extruder Body from this Thing:

[www.thingiverse.com]

I am using the gears from that thing as well although I plan on upgrading to some herringbone gears.

I am also not using the idler in that thing. I am using a guidler from here:

[www.thingiverse.com]

I am going to be using these dino's when I upgrade to the J-Head hot end:

[www.thingiverse.com]

None of this is possible without a stepper extruder driver mod to the Gen3 electronics, though, or by upgrading entirely. My Ramps powered cupcake is printing better than it ever has. My cupcake is well on it's way to being heavily modified.

That's very helpful. Thanks for sharing. My DC motor died last week, so I had some decisions to make whether to do incremental upgrades or a radical change to a 1.75mm extruder like [store.qu-bd.com] or even a OneUp kit [store.qu-bd.com]

I thought staying with 3mm might make more sense since I still have filament to consume so it's great to know this option has a Jhead upgrade path when I'm ready.
1) I have a high holding torque nema17 stepper [cgi.ebay.com] on the way, along with
2) a DRV8825 based pololu driver. [cgi.ebay.com]
3) I was intending to do the ugly cable hack (really just direct solder to the pololu board) if I can't find a source for the gen3+ board in the US. The Lulzbot site charges $14.53 shipping for a $8 PCB and I haven't gotten that desperate yet.
4) I even got a hobbed M8 bolt which I assume would be appropriate for the extruder parts you listed above. [cgi.ebay.com]
5) I just need to find someone in Maryland who can print the parts for me, or find a trustworthy online source.

Would these parts get me close enough? I just need the cheapest/quickest path back to printing and can figure out the upgrades from there.
[cgi.ebay.com]
I can't tell if I only need to buy the springs and bolts for the idler and reuse bearings from the MK5, or if I needed more vitamins. What new items did you have to buy?

TIA!

Edited 1 time(s). Last edit at 01/11/2014 08:10AM by bzbee.

The gen 3+ board I'd only compatible with the old gen3 motherboard with integrated stepper drivers, from what I found out. Do you have that one or the the MakerBot red electronics? I believe you really need a 3g5d shield which I have been unable to find. Also is your dc motor really dead? Have you applied 12v directly to it. Mine"died" too until I realized that it wasn't dead it was just that the ec board couldn't run the motor due to the motors low resistance. I constructed a mosfet based circuit to act as a power relay where the ec board merely was the switch tuning the most on/off. See here [rayshobby.blogspot.com]. This circuit worked beautifully and allowed me to print.

What parts you want printed? Ever hear of "print it forward"? I'll print you some parts if you print it forward.

The extruder will need two? M4x50 bolts, 4 M4 washers, M4 plain nuts, one 608 skate bearing, one small length of M8 rod about an inch long, one M3 plain nut, one M3 and one M3x25 bolt. We may be able to work out an agreement for that stuff too if you want. I have it all.

Edited 2 time(s). Last edit at 01/11/2014 08:57AM by umdpru.

Thanks so much for your offer of assistance. I have a local friend who has already offered help (plus I get to tweak his print quality in person), but I will keep it in mind and PM you if so. I did not know about the relay fix, but I am intent on upgrading to the stepper extruder no matter what at this point so I'd rather apply my limited funds toward that goal than get sidetracked. The Greg's Hinged Extruder on eBay looks like the same setup as the parts you listed. [cgi.ebay.com] I'm very much tempted to just spend the $12 since I have some eBay Bucks and credits to use. I will PM the Ebay seller to confirm.

The Gen3+ acts as a Sanguino shield, so should work with the Gen 3 electronics that came with the Cupcake.

I don't really need it, but it seemed like an elegant solution with some degree of modularity without adding more stray wires into the already messy affair.

Thanks for the BOM. This is one of those cases where there is too much information out there that is sometimes at odds, so I appreciate the info from someone who just went through it themselves.

No problem, let me know how you make out. I just now started printing out an extruder block as a backup! Always have extruder parts backups. I don't have the luxury of another local printer until I get my MakerFarm Prusa I3 in.

I read on the forums, I can't find where now, that the Gen3+ board was for an even earlier version Gen3 motherboard that had the stepper drivers integrated directly onto the motherboard rather than separate components. That's why I decided not to purchase it. Wish I had known that it would have worked. I still have the Gen3 mobo and I might decide to get it working again, I don't know. It's only half stepping capable so I don't know. That's kind of a deal killer now that I'm running ramps 1.4.

That listing does look like the same extruder. there are so many remixes that it's hard to tell. I'm printing one right now that allows a bit easier access to the filament for changing by allowing the guidler screws to tilt up rather than removing them completely. I'd go for that one though! You'll have to custom drill it to fit the Cupcake dino's, though. I could only fit three bolts in. Of course, you could also print a new mounting plate out, though.

What hot end are you using right now? I'm still using the Mk5 plastruder hot end. It's printing well so I'm not going to touch it. When I tear down the extruder next time, I'll replace it with the J-Head I have now.

The best part about going to a stepper extruder was the complete elimination of stringing!!!

Edited 1 time(s). Last edit at 01/11/2014 10:43AM by umdpru.